Referring to FIGS. 5 to 7, a conventional automobile tail light device includes a shell 5 and two light emitting modules 6. The shell 5 has a housing 51 and a light shade 53 cooperatively defining an accommodation chamber 52, and a support frame 54 disposed in the accommodation chamber 52 and having two holding holes 541 for holding the light emitting modules 6. Each light emitting module 6 includes a base seat 61, a control board 62 mounted on the base seat 61, a plurality of light emitting members 621 mounted on and controlled by the control board 62, a light guiding seat 63 mounted on and extending rearwardly from the base seat 61 to surround the light emitting members 621 to define a light guiding space therein, a reflector plate 64 mounted in the light guiding space, an annular frame 65 attached to an inner surface of the light guiding seat 63, and a semi-translucent plate 66 disposed in the annular frame 65 and spaced apart from the reflector plate 64.
Such light emitting module 6 has a large number of component parts, which are required to be individually mounted in sequence in the accommodation chamber 52, thereby rendering the assembly task inconvenient.